1. Field of the Invention
The invention relates to a novel combination of compounds and the use of this composition for enhancing or imparting cooked tomato flavor to food products.
2. Background Art
The tomato processing industry is one of the largest in the food area. A major portion of the tomato crop in California is converted to tomato paste. This forms a relatively stable concentrated form of processed tomato that can be marketed in this form or used in the preparation of a great variety of processed tomato products such as tomato sauce, spaghetti sauce, pizza sauce, steak sauce, tomato soup, tomato juice, and ketchup. In addition to tomato paste, other forms of processed tomatoes are used in food products. For example, dehydrated tomatoes are used in soups, spaghetti sauce, and the like.
In the food industry it is well recognized that flavor and aroma play a critical role in the value of food products for consumption. It is also recognized by those skilled in the art of food flavors that aroma is responsible for the major part of flavor (see Progress In Flavor Research, Ed. D. G. Land and H. E. Nursten, Applied Science Publishers Ltd., London (1979), page 53).
Desirable cooked tomato flavor and aroma is that associated with high quality tomato paste. Difficulties in consistently obtaining such flavor and aroma are due to: (1) variations in raw materials, (2) loss of flavor and aroma volatiles during processing steps, e.g., heating, canning, freezing, or dehydydration, and (3) loss of flavor during storage. As a consequence, a processed tomato food product may be lacking in the desired cooked tomato flavor.
Tomato aroma volatiles comprise a complex mixture of components which provide the characteristic odor and flavor of tomatoes. A review article by M. Petro-Turza (Food Reviews International 2:311-353 (1986)) lists over 400 compounds that have been identified in the volatiles of tomato and tomato products. During the processing of tomatoes, changes in the composition of tomato volatiles occur. J. C. Miers (Journal of Agricultural and Food Chemistry 14: 420-423 (1966)) and Guadagni and Miers (Food Technology 23: 101-103 (1969)) reported increases in dimethyl sulfide during the heat treatment of tomatoes and provided evidence of the importance of dimethyl sulfide to tomato juice aroma. R. G. Buttery et al. (Journal of agricultural and Food Chemistry 19: 524-529 (1971)) listed 100 compounds identified in tomato volatiles with some certainty and characterized additional volatile components of fresh and heated tomatoes. The researchers concluded that no single or small group of compounds is entirely responsible for the characteristic aroma of fresh or cooked tomatoes.